html,
body {
  max-width: 720px;
  overflow: hidden;
  margin: 0 auto;
}

.header {
  height: 55px;
}

.footer {
  height: 55px;
}

.footer-seat {
  position: fixed;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 55px;
}

.footer-list {
  max-width: 720px;
  height: 55px;
  margin: 0 auto;
  background-color: #999;
}

.footer-list ul {
  display: flex;
  height: 100%;
  justify-content: center;
  align-items: center;
}

.footer-list ul li {
  flex: 1;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  width: 33.33%;
  height: 100%;
  color: #fff;
  font-size: 12px;
  text-align: center;
  cursor: pointer;
}

.footer-list ul li i {
  font: 700 24px arial;
  padding: 5px 0;
}

.footer-list .selected {
  color: #2D75FE;
}